Congestive heart failure (CHF) is divided into two types: chronic CHF and acute (or decompensated-chronic) CHF. Chronic CHF is a longer term, slowly progressive degenerative disease clinically categorized by the patient's ability to exercise or perform normal activities of daily living. CHF can be ischemic, heart muscle damage that results from coronary artery disease, such as heart attack, or non-ischemic, not related to coronary artery disease. CHF is further subdivided according to abnormalities in the cardiac cycle: namely, systolic heart failure (SHF) and diastolic heart failure (DHF). Both SHF and SHF have ventricular remodeling, but the characteristic difference is that in DHF there is not an increase in end diastolic volume, which describes the remodeling in SHF. While the left ventricle in SHF is dilated, compliant, and poorly contractile, the ventricle with DHF is small, stiff, and often hyperdynamic. With the arterial stiffening and hypertension which often accompany successful aging, the incidence of DHF is believed to account for 50% of the 4.6 million US citizens with congestive heart failure and of those hospitalized for congestion. The typical patient with DHF is quite different from the patient with SHF.
The identification of patients with CHF is done based on history and a physical examination during which the condition is often characterized by various signs and symptoms of intra-vascular and interstitial volume overload, including shortness of breath, irregular heart rate, abnormal heart rate and signs of edema. The use of biomarkers in evaluating heart failure may provide another way to identify patients. Brain natriuretic peptide or BNP is the most commonly used biomarker for diagnosing heart failure. It is released in response to ventricular stretch and is considered a marker for myocardial stress. While BNP is released primarily in the heart ventricles during hemodynamic overload, it is also released from brain, lungs, kidneys, and vascular tissues. It has been used most commonly in diagnosing systolic heart failure. Levels of BNP levels tend to be lower in diastolic heart failure, and its utility in assessing these patients is under evaluation.
There remains a need for new biomarkers suitable for the identification of biomarkers suitable for detecting and/or diagnosing congestive heart failure including systolic and diastolic heart failure, ischemic and non-ischemic heart failure.